Patent EA-002260-B1 (EA)
Title: Device for preheating charging stock, comprising replaceable stack wall sections
Inventor: FUCHS GERHARD
IPC: F27B3/18
Filed: 1999-02-19
Abstract: 1. A charging material preheater for preheating charging material (60) which is to be charged into a furnace vessel (3), in particular metal scrap, having a shaft (9) which is fixed in a frame structure (20) and which in its upper region has a closable feed opening (61) for the charging material (60) and a gas outlet (32) and in its lower region a discharge opening for the charging material (60) and a gas inlet, and whose shaft walls (32 to 37) delimit a receiving space (62) for the charging material (60) to be heated, characterised in that at least one of the shaft walls (34 to 37) is subdivided into shaft wall portions (34/1, 34/2 to 37/1, 37/2) which are individually fixed in the frame structure (20) and are individually replaceable. 2. A charging material preheater according to claim 1 characterised in that the respective shaft wall (34, 35) is subdivided in a perpendicular direction into at least two shaft wall portions (34/1, 34/2; 35/1, 35/2) which are arranged one above the other. 3. A charging material preheater according to claim 1 or claim 2 characterised in that the respective shaft wall (34, 35) includes at least one first shaft wall portion (34/1, 35/1) which is in the form of a steel wall element (70) which can be cooled by a forced cooling apparatus. 4. A charging material preheater according to claim 3 characterised in that the steel wall element is in the form of a fluid-cooled tubular panel. 5. A charging material preheater according to claim 4 characterised in that the tubular panel is formed by tube portions which are disposed in mutually juxtaposed relationship and which extend parallel to the direction of movement of the charging material upon filling and emptying of the shaft. 6. A charging material preheater according to claim 3 characterised in that the steel wall element is in the form of a cast steel plate and the temperature of the cast steel plate is controllable by the forced cooling apparatus in dependence on a temperature measurement value of the cast steel plate, which value can be detected by at least one temperature sensor. 7. A charging material preheater according to one of claims 1 to characterised in that the respective shaft wall (34, 35) includes at least one second shaft wall portion (34/2, 35/2) which is in the form of a refractory wall element and which, on the inside which is towards the receiving space (62) for the charging material (60), is formed by a layer or plate (71) of refractory material. 8. A charging material preheater according to claim 7 characterised in that the refractory wall element has a fluid-cooled outside (72). 9. A charging material preheater according to claim 7 or 8 characterised in that the refractory wall element is formed by a sheet metal plate member (73) with edges which are angled towards the shaft interior and into which is fitted a refractory lining (71). 10. A charging material preheater according to one of claims 3 to 9 characterised in that the fluid-cooled shaft wall portions are connectable to cooling circuits of the forced cooling apparatus, which can be individually taken out of operation. 11. A charging material preheater according to one of claims 1 to characterised in that the shaft wall portions (34/1, 34/2; 35/1, 35/2) have at their outside support surfaces (74) which are supported on cooperating counterpart mountings (76) of the frame structure (20). 12. A charging material preheater according to one of claims 1 to 11 characterised in that first shaft wall portions (34/1 to 37/1) are provided in the lower region of the shaft (9) and second shaft wall portions (34/2 to 37/2) are provided in the upper region of the shaft. 13. A charging material preheater according to one of claims 1 to 12 characterised in that the frame structure (20) is in the form of a cage structure (63 to 69) which surrounds the shaft walls (34 to 37). 14. A charging material preheater according to one of claims 3 to 13 having a shaft (9) which in its lower region has retaining members (54, 55) for the charging material to be heated. which are formed by fingers (54) which are arranged parallel and at a spacing from each other and which are mounted in rotary mountings (56) and which are pivotable downwardly from a closed position in which inner portions of the fingers (54) project inclinedly downwardly into the interior of the shaft to block the passage of charging material therethrough, into a release position in which said portions of the fingers (54) point downwardly and release the charging material to pass through. characterised in that the shaft wall (34) which is towards the inner ends includes one or more first shaft wall portion in the region which is subjected to a particular mechanical loading due to the resilient return movement of the fingers when the shaft is loaded. 15. A smelting unit having an arc furnace (1) which includes a furnace vessel (3) with a vessel cover (4) comprising first and second cover portions (7, 8) of which the first cover portion (7) includes at least one electrode opening (14) for the introduction of an electrode (12) and the second cover portion (8) includes a shaft (9) which is fixed in a holding arrangement (21), characterised in that the shaft (9) is constructed according to one of the claims 1 to 13 and the holding arrangement (21) and the vessel (3) are displaceable horizontally relative to each other. 16. A smelting unit according to claim 15, characterized in that the frame structure (20) carrying the shaft (9) is mounted in such a way that it can be raised/lowered in the holding arrangement (21).